"Getting stuck on the swells" - is this happening when you go across the waves on one tack or when you go straight in to them (depending on the wind direction I guess). It's fairly common on this board to get the sensation of being a little stuck on the swells as you go across them; I would keep the mast track all the way in the back on both the 11 and the 12 to combat this and get the nose lifting.
I don't know too much about the FRB7 fin from Otmar but I assume it's pretty powerful? What rake do you have the fin at?
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